BTJ 6/17 - Is it worth it? Making the Baltic, the North Sea, and the English Channel a Nitrogen Emission Control Area

However, when released during fuel combustion, it binds together with oxygen to form nitric oxide (NO), which again isn't a hazardous compound (at least when it occurs at standard ambient concentrations).

Combined once more with oxygen, NO transforms into nitrogen dioxide (NO2), long-term exposure to which may decrease lung function and increase the risk of respiratory symptoms.

What's more important, though, is that both compounds are surrogates to other and far more dangerous pollutants, most notably particle matter (PM) and ground-level ozone (03), which lead to respiratory and cardiovascular diseases, or in short - increased mortality.